Problem: Simplify the following expression: ${-2q+3(q+7)}$
Distribute the ${3}$ into the parentheses: $ -2q + {3(}\gray{q+7}{)} $ $ -2q + {3q+21} $ Combine the $q$ terms: $ {-2q + 3q} + 21$ $ {q} + 21$ The simplified expression is $q+21$